WO2015132126A1

WO2015132126A1 - Endoscope featuring depth ascertainment

Info

Publication number: WO2015132126A1
Application number: PCT/EP2015/054036
Authority: WO
Inventors: Peter Rentschler; Anton Schick
Original assignee: Siemens Aktiengesellschaft
Priority date: 2014-03-07
Filing date: 2015-02-26
Publication date: 2015-09-11
Also published as: KR20160129898A; CN106102544A; EP3113665A1; US20170014030A1; JP2017508530A; DE102014204244A1; KR101867380B1

Abstract

Disclosed is an endoscope (1) for ascertaining the depth of a subregion (50) of a cavity, comprising at least one imaging channel (21) which has a first optical axis (101) and in which at least one first optical deflection device (31) is arranged, said optical deflection device (31) being designed to transversely offset the first optical axis (101) parallel to the first optical axis (101).

Description

description

Endoscope with depth determination The invention relates to an endoscope for depth determination of a partial region of a cavity.

The number of minimally invasive operations has steadily increased in recent years. In minimally invasive surgery endoscopes (3D endoscopes), the one that sets ^¬ a depth determination in a patient to be examined cavity while allowing an imaging method is. According to the prior art, for the depth determination of the cavity, for example, an abdominal space of the patient, a plurality of ports (ports) are placed.

The additions to the cavity (observation area), which are formed as access channels are typically very narrowly defines ^¬. This is the case because the patient should be operated on as gently as possible in minimally invasive surgery. Due to the narrow channels, the design of 3D endoscopes is severely limited. According to the prior art known 3D endoscopes are in this case designed as a cylindrical, Läng ^¬ liches tube.

According to the prior art further optical Comp ^¬ components are provided for the depth determination of the cavity by means of a 3D endoscope that allow active or passive triangulation of the cavity and thus a depth determination. Decisive for the resolution of the depth determination in active or passive triangulation is the size of a Triangulationsbasis. The triangulation in this case denotes the distance of a projector and an optical imaging ^¬ system in the endoscope. The larger the triangulation base, the better the resolution of the depth determination.

In order to achieve sufficient for minimally invasive surgery Abbil ^¬-making performance, according to the state of the art mostly optical imaging systems used, which have a relatively large cross-section. As used in minimally invasive surgery ver ^¬ can not be dispensed at a sufficiently high image quality, thus the triangulation must be reduced accordingly, thus reducing the resolution of the depth determination.

The present invention is therefore based on the object to improve the optical depth determination of an endoscope.

The object is achieved by a device having the features of independent claim 1. In the dependent claims advantageous refinements and developments of the invention are given.

According to the invention, an endoscope for depth determination of a partial region of a cavity is proposed which comprises at least one first imaging channel, which first imaging channel has a first optical axis, wherein at least one first optical deflection device, which is relative to the first optical axis, is arranged within the first imaging channel transverse parallel offset of the first optical axis is formed.

According to the invention the endoscope includes a first optical To ^¬ steering apparatus that enables a first optical axis of the first Ab formation ^¬ channel transversely parallel. The first optical axis of the imaging channel can be a Sym ^¬ metrieachse a reflective or refractive optical element. If the imaging channel comprises a lens and / or imaging system, the first optical axis is the optical axis which is formed by the optical axis of the optical individual elements.

Advantageously, by means of the inventive trans ^¬ parallel parallel offset of the first optical axis mit- means of the first optical deflecting an enlargement of a triangulation of the endoscope according to the invention it ^¬ made possible. In this case, the transversal parallel offset of the first optical axis is expediently to be provided in such a way that an enlargement of the triangulation base takes place. By increasing the triangulation of the endoscope, the resolution of the depth determination (low resolution) is improved in part by way of legally before ^¬. In particular, in order to improve the depth resolution, the endoscope and / or the first imaging channel need not be reduced in size compared to endoscopes known from the prior art, although the triangulation base is increased. This beneficial ^¬ way legally does not affect the imaging performance known endoscopes.

The transverse parallelism of the offset of the first optical axis ^¬ rule is approximately understand. It is crucial that the triangulation is enlarges comparable by means of the displacement, which takes place by means of the first optical deflecting device ^¬ rule. In other words, the first optical Um ^¬ steering device is designed to increase the Triangulationsbasis.

Preferably, the first optical deflection device is arranged at a distal end of the endoscope.

Typically, a beam diameter of a bundle of light entering the imaging channel at the distal end of the endoscope is small, since strong bundling of light beams, which form the light bundle, takes place upon entry into the first imaging ^{channel of} the endoscope. Thus, the space requirement for the first optical To ^¬ steering apparatus is part way legally reduced before ^¬. According to an advantageous embodiment of the invention, the first imaging channel to a lens, wherein the objek ^¬ tively comprises the first optical deflection device. Here, it is preferable that the first optical Umlenkvor ^¬ direction with respect to an incoming channel in the first image light beam, is arranged behind a first lens of the objective. Particularly preferred is an objek- tive, which is designed as a wide-angle lens. In this case, a light bundle entering the first imaging channel is bundled in a pupil. Advantageously, the first op ^¬ diagram deflecting device is arranged in an area of the pupil, so that this can be made small, the first deflection with regard to their geometric extensions, as the pupil of the incident image on the first channel the light beam is also small.

According to an advantageous embodiment of the invention, the first imaging channel comprises further lenses.

Preferably, the first imaging channel comprises a lens system, which lens system comprises a plurality of lenses. As a result of the arrangement of at least one lens in the imaging channel, an optical imaging system is consequently arranged in the first imaging channel. Here, the image of the Teilbe ^¬ realm of the cavity via the first channel by means of illustration of the lens respectively by the optical imaging system ^¬ takes place. By way of example, the lens can be designed as a collimator, a scattering lens or as a focusing lens. ^Further optical components, for example mirrors, glasses, crystals, beam splitters, Faraday isolators and / or prisms can be provided. For example, an additional angle change of the first optical axis can be provided by means of said optical components. The angle change is preferably in the range of 1 ° to 5 °, more preferably a Winkelän ^¬ tion is less than or equal to 3 °.

Preferably, the first imaging channel of the endoscope comprises a further lens, which is designed as a relay lens. Typically, relay lenses are used in a transfer of the image from the distal end of the endoscope to an opposite end of the dista ^¬ len other end of the endoscope.

According to an advantageous embodiment of the invention, the first optical deflection device is formed as a parallelepiped from ^¬ . Here, the parallelepiped or the first op ^¬ tables deflection device is arranged such that by reflections within the parallelepiped, one in the

Parallelepiped incoming light beam, the transverse parallel displacement of the light beam results. In other words, the first optical deflecting device is designed as a kind of Pris ^¬ menblock wherein nenflächen by a double reflection, in particular by a two-time total reflection of a ^¬ impinging light beam, the incident in the first image channel at the distal end of the endoscope light beam at home the first optical deflection device is offset transversely parallel. Due to the transverse displacement of the parallel light beam advantageously Triangu ^¬ lationsbasis of the endoscope is increased, whereby the resolution of the depth determination is improved. Here, the transverse parallel offset of the light beam corresponds to the transverse parallel offset of the first optical axis.

Favor is a first optical deflection device, insbeson ^¬ particular a parallelepiped having at least two mirrored nenflächen home.

By means of the mirrored inner surfaces of the first optical deflection device, the light beams entering the first imaging channel are reflected at least twice within the first optical deflection device, in particular totally reflected. This enables the transverse parallel displacement of the first optical axis by means of the first optical deflection device. Here it is intended hen, based on the light entering the first imaging channel ^¬ light rays, in front of the first optical deflection further optical components, such as lenses and / or lenses are arranged. In a particularly effi- cient embodiment, the first optical deflecting device comprises two individual mirrors, which form two sides of a ge ^¬ thought parallelepiped.

According to a particularly preferred embodiment of the invention, the endoscope comprising a projection channel, wherein the Pro ^¬ jektionskanal comprises a projection apparatus which is designed for projecting a pattern on a surface of the portion of the cavity. Advantageously, the arrangement of at least one projection channel in the endoscope enables active triangulation of the partial region of the cavity. In this case, structured light, in other words, a pattern sheet to a surface of the portion of the cavity proji ^¬ by means of the projection device, which is arranged in the projection channel. By means of the projected pattern, in particular by means of a coded pattern is advantageously weakened in the active triangulation a Korres ^¬ pondenzproblem or even completely dissolved.

Particularly preferred is a projection ^{device that} summarizes a diffractive optical element for generating the pattern ^¬ . Advantageously, a DOE projector is formed by a projection device comprising the diffractive optical element. A DOE projector is hereby regarded as a projection device comprising a diffractive optical element (abbreviated to DOE). Since DOE proj ectors, in contrast to projectors, which typically have a slide for the production of the pattern, have a smaller space requirement, the projection channel with a relatively small diameter or a comparatively small Cross-sectional area are formed. In particular, the cross-sectional area of the projection device or the projection channel is less than or equal to 2 mm ² . Overall, a space-saving active triangulation of the partial area of the cavity is made possible by the projection channel, the first imaging channel and the projection device arranged in the projection channel, which comprises a diffractive element.

Particularly preferred is an active triangulation, which takes place by means of a color-coded pattern.

In other words, the endoscope allows active color-coded triangulation of the portion of the cavity. In a further preferred embodiment of the invention, the projection channel is optically coupled to a light source.

Particularly preferred are a laser or a light emitting diode (LED) as the light source. In this case, a single-mode fiber can be provided for the optical coupling of the projection channel with the light source, in particular with the laser. In the monomode laser, exactly one light mode, the fundamental mode, is advantageously guided, so that interference between a plurality of light modes, which could lead to a disturbance of the projected pattern, is avoided.

By means of the single-mode fiber is thus the light of the Lichtquel ^¬ le, in particular of the laser, incorporated ^¬ passes in the projection channel. In this case, the wavelength of the laser for optimum dot contrast generation, for example in the blue spectral range, can be adapted to the application in minimally invasive surgery. It is particularly preferred that, for example with an interference filter, a disturbing influence of daylight and / or artificial light is reduced by the use of a laser as the light source.

According to an advantageous embodiment of the invention, the endoscope comprises an instrumentation channel. Advantageously, surgical tools, which are required for minimally invasive surgery, can be introduced into the cavity by means of the instrumentation channel. The arrangement of a diffractive optical element in the projection channel saves installation space, which in turn can be used for the instrumentation channel. In particular, a plurality of instrumentation channels may be provided. In a particularly advantageous embodiment of the invention, the endoscope comprises a second imaging channel extending parallel to the first imaging ^channel , which second imaging channel has a second optical axis, wherein within the second imaging channel a second optical deflection device is arranged, which is relative to the second optical Axis transverse parallel offset of the second optical axis is formed.

Advantageously, through the second imaging channel, which has a second optical deflection device, a

Stereoscopy of the portion of the cavity allows. Be ^{¬ is} particularly advantageous that is increased by the first and the second optical deflection the Triangulationsbasis against a known in the prior art endoscope for stereoscopy. As a result, the resolution of the depth determination of the partial region of the cavity is advantageously improved by the endoscope proposed here. In this case, a second imaging ^channel designed in accordance with the first imaging ^{channel is} provided.

Particularly preferred is a second imaging channel whose second optical deflection device has a direction of transverse parallel displacement which is opposite to the direction of the transverse parallel displacement of the first optical axis. This advantageously the triangulation wei ^¬ ter increased, so that the resolution of the depth determination is further improved. In a particularly preferred embodiment of the invention, the second imaging ^{channel is ausgebil ¬} det as a projection ^channel .

In general, each imaging channel can be used as a projection channel. Advantageously, an active triangulation of the portion of the hollow ^¬ space is made possible by the Projection ^¬ channel. If the endoscope has two imaging channels and one projection channel, an active stereoscopy of the partial region of the cavity can take place with the endoscope.

According to one embodiment of the invention, the endoscope has an observation angle of 30 °. Here, an arrangement of the first optical deflection device within the endoscope, which has an observation angle of 30 ° (30 ° -Endoscopes), is provided.

Further advantages, features and details of the invention follow from the ^¬ described in the following embodiments and from the drawings. Showing:

Figure 1 is a schematic sectional view of a first

An imaging channel comprising a first optical deflection ^¬ device;

FIG. 2 shows a further schematic sectional view of a first imaging channel comprising relay lenses;

Figure 3 is a schematic sectional view of an Endo ^¬ Skops having a first and a second image channel; Figure 4 is an enlarged view of the gezeig th in Figure 3 endoscope. and

Figure 5 is a schematic sectional view of an Endo ^¬ Skops comprising a first image channel and a projection channel.

Similar elements may be provided with the same reference numerals in the figures.

In Figure 1, a first image channel 21 of an endoscope 1 does not represent ^¬ provided is schematically illustrated. Here, an objective 2 is arranged in the first imaging channel 21, which objective 2 has a first optical axis 101. To a transversely parallel offset 42 of the first optical axis 101 of the lens 2, a first optical Um ^¬ steering device 31 is provided according to the invention. In this case, the first optical deflection device 31 is arranged with respect to light rays 10 arriving in the first imaging channel 21 after a first lens 14 of the objective 2. In other words, the first optical deflection device 31 is integrated into the Whether ^¬ objectively second When integrating the first optical deflecting device 31 into the objective 2, therefore, changed characteristics of incoming light beams 10 are to be taken into account. The objective 2 and consequently also the first optical deflection device 31 are arranged at a distal end 4 of the endoscope 1, not shown. By means of the deflection device 31, the light beams 10 (light beam) arriving in the first imaging channel 21 are deflected or displaced such that preferably a transverse parallel offset 42 of the light beams 10 results. In the exemplary embodiment shown in FIG. 1, the first optical deflection device 31 is designed as a parallelepiped and has at least two inner surfaces 12 for deflecting the incident light beams 10. Here ^¬ which the incoming light beams 10 on the inner surfaces 12 the first optical deflection device 31 is reflected, in particular totally reflected.

An essential advantage of the first optical deflection device 31 is that these, for example, in comparison to

Relay lenses 8 (two shown in Figure 2), only has a small space requirement. In particular, the geometric dimensions of the first optical deflection device 31 are smaller than the geometric dimensions of typical imaging channels. Thereby, the first optical deflecting device 31 advantageously be ^¬ known per in existing endoscopes imaging channels can be arranged without the geometrical dimensions of the imaging channels of the endoscopes or less favorable ^¬ tig enlarge. Also an arrangement of the first optical deflection device 31 within an endoscope having a Be ^¬ obachtungswinkel of 30 ° (30 ° endoscopes) is thinking ^¬ bar.

In the exemplary embodiment of the endoscope 1 shown in FIG. 1, the first optical deflection device 31 is arranged with respect to the incident light beams 10 after the first lens 14 of the objective 2. However, a first opti ^¬ cal deflection 31 may be provided, which is not part of the lens 2 and is therefore arranged before or after the Objective 2. For example, an arrangement according to the objective 2 is advantageous if an exit pupil of the objective 2 lies in the distal direction in front of the objective 2. Furthermore, a camera, in particular a three-chip camera, may be provided in the first imaging channel 21. In this case, it is possible to integrate the camera, objective 2 and the first optical deflection device 31 in a chip, so that an arrangement which saves as much space as possible is created.

FIG. 2 shows a further schematic sectional illustration of a first imaging channel 21 along an axis of symmetry (Endoscope axis) of a cylindrical endoscope 1, not shown.

Relationship as loading at a distal end 4 of the first image channel 21 of the endoscope 1, a first optical deflection ^¬ device 31 is disposed within a lens 2, wherein the first optical deflection device 31 with respect to entering into the first imaging channel 21 light beams 10 of according to a first lens 14 Objective 2 is arranged.

As already shown in Figure 1, is the first op ^¬ diagram deflection device 31 which is ausgebil ^¬ det as a parallelepiped, a transversal parallel shift 42 allows an optical axis of the one hundred and first In the exemplary embodiment illustrated in FIG. 2, the first optical axis 101 relates to the optical axis of further lenses of the objective 2, which are arranged downstream of the first optical deflection device 31 with respect to the incoming light beams 10 and / or on the optical axis of the imaging channel 21 arranged Relaylinsen 8. Here, the arranged in the first imaging channel 21 relay lenses 8 form a so-called first

Relay stage 6 of the first imaging channel 21 from.

Typically, the relay lenses 8 and consequently the first relay stage 6 have a greater geometric extent than the first optical deflection element 31. In other words, the geometric extension, in particular a diameter of the imaging channel 21, is not limited by the first optical deflection ^¬ device 31, but by the arranged in the first imaging channel 21 relay lenses 8. Consequently, a smallest geometric extension of the first imaging channel 21 is arranged through the first imaging channel 21

Relay lenses 8 given. Advantageously, no enlargement of the first Ab ^¬ education channel 21 is necessary for the arrangement of the first optical deflection device 31 in the first imaging channel 21. FIG. 3 illustrates a schematic sectional illustration of an endoscope 1, wherein the endoscope 1 comprises a first imaging ^channel 21 and a second imaging channel 22.

Both in the first and in the second imaging channel 21, 22, a lens 2 is arranged. In this case, it can be provided that a camera for recording the images of the first and second imaging channels 21, 22 is arranged within said imaging channels 21, 22 and / or is integrated directly into the lenses 2 mentioned. The ers ^¬ te and second imaging channel 21, 22 and the lenses 2 ei ^¬ ne first and second optical deflection device 31, 32. Based on in the imaging channels 21, 22 at a distal end 4 of the endoscope 1 entering light beams 10, is Before the first and the second optical deflection device 31, 32 each have a first lens 14 of the respective lens 2 before ^¬ seen. In this case, the first and second imaging channels 21, 22 form an image of a partial area 50 of a cavity from different viewing directions. This advantageously a stereo copy of the portion 50 made ^¬ light. The first and second deflection device 31, 32 in ers ^¬ th and second imaging channel 21, 22 are such angeord- net that in each case a directed against transversal parallel shift of the light beams obtained 10th Thereby advantageously a triangulation of the endoscope 1, not shown, whereby the resolution of the depth ^¬ determination of the portion 50 of the cavity is improved is increased.

FIG. 4 shows an enlarged view of the endoscope 1 shown in FIG. Again, at a distal end 4 of the endoscope 1 in the first and second Abbil- dung channel 21, 22 each have a lens 2, an optical To ^¬ steering apparatus 31, 32 and a first lens 14, the lenses. 2 The first imaging channel 21 has a first one optical axis 101 and the second imaging channel 22 has a second optical axis 102.

Arranged at the distal end 4 of deflection devices 31, 32 allow magnification of an original triangulation known endoscopes 44, wherein the Original Art ^¬ surface triangulation is set to 44 by the distance of the first and second optical axis 101, the 102nd The first optical deflection device 31 has a parallel transverse displacement 42 of the first optical axis 101, opposite to a parallel transverse displacement 43 of the second optical axis 102, wherein the transverse pa ^¬ rallele offset 43 of the second optical axis 102 by means of the second optical deflection device 32 is possible. Overall, this results in a triangulation base 46, which is enlarged compared to the original triangulation base 44. As a result, the resolution of the depth determination of the endoscope 1 is advantageously further improved. Have the imaging channels 21, 22 an additional Winkelän ^¬ alteration of their optical axes 101, 102, so can be carried out a steering of the light beam in such a way by means of the change in angle of an incoming in said channels 21, 22 the light beam that principal rays of the light beam on an axis of the endoscope in a center of the lenses 2 (pupil) intersect. Thereby, an offset of the images between the first and second imaging channels 21, 22 is reduced.

FIG. 5 illustrates a schematic sectional view of an endoscope 1, which comprises a first imaging channel 21 and a projection channel 16. In this case, a projector 18 is arranged within the projection channel 16, which comprises a diffractive optical element (DOE). Such a projector 18 is referred to as a DOE proj ector. This makes an active triangulation by means of a color-coded

and / or dot-coded pattern. At a distal end 4 of the endoscope 1, a first Um ^¬ steering device 31 is arranged, which allows an enlarged Triangu ^¬ lationsbasis 46. For this purpose, a first optical axis 101 is offset transversely 42. An original trian- gulation base 44 is thereby advantageously increased. Based on light beams 10, which enter the first imaging channel 21 at the distal end 4, a first lens 14 of the objective 2 is arranged in front of the first optical deflection device 31, so that the first optical deflection device 31 between the first lens 14 and further lenses of the objective 2 is arranged. Here, the first optical axis 101 is determined by said further lenses of the lens 2. The projection channel 16, the first and / or second Abbil ^¬ dung channel 21, 22 may further optical components, play, in ^¬ lenses, mirrors, gratings, beam splitters and / or prisms and / or all of the optical devices, such as additional lenses comprise. In particular, the ERS te and / or second imaging channel 21, 22 may be formed by means of a Whether ^¬ jektivs. Here, a camera, ^¬ example, a three-chip camera on the lens 2 is arranged and / or in the lens 2 may be integrated. In this case, the images are preferably transmitted via optical fibers, in particular by means of a monomode fiber.

Although the invention has been further illustrated and described in detail by the preferred embodiments, the invention is not limited by the disclosed examples, or other variations can be derived therefrom by those skilled in the art without departing from the scope of the invention.

Claims

claims

1. endoscope (1) for depth determination of a partial area (50) of a cavity, the at least one first image channel (21) having a first optical axis (101), includes fully, wherein within the first image channel (21) we ^¬ nigstens a first optical deflection device (31) is angeord ^¬ net, which is formed to a relative to the first optical axis (101) transversely parallel offset (42) of the first optical axis see (101).

2. Endoscope (1) according to claim 1, characterized in that the first optical deflection device (31) at a dis ^¬ tal end (4) of the endoscope (1) is arranged.

3. endoscope (1) according to claim 1 or 2, characterized in that the first imaging channel (21) comprises a lens (2), wherein the lens (2) comprises the first optical deflection ^¬ device (31).

4. endoscope (1) according to one of the preceding claims, characterized in that the first imaging channel (21) comprises at least one lens (8).

5. endoscope (1) according to one of the preceding claims, with at least one relay lens (8).

6. endoscope (1) according to one of the preceding claims, characterized in that the first optical deflecting device (21) is designed as a parallelepiped.

7. endoscope (1) according to one of the preceding claims, characterized in that the first optical Umlenkvor ^¬ direction (21) has at least two mirrored inner surfaces (12).

8. Endoscope (1) according to one of the preceding claims, with a projection channel (16), wherein the projection channel (16) a projection device (18), which is designed to pro jection ^¬ a pattern on a surface of the portion of the cavity.

9. endoscope (1) according to claim 8, characterized in that the projection device (18) comprises a diffractive opti ^¬ cal element for generating the pattern.

10. endoscope (1) according to claim 8, characterized in that the pattern is a color-coded color pattern.

11. Endoscope (1) according to one of claims 8 to 10, characterized in that the projection channel (16) is optically coupled to a light source.

12. Endoscope (1) according to one of the preceding claims, with a Instrumentierkanal.

13. Endoscope (1) according to one of the preceding claims, with a second imaging channel (22) having a second opti ^¬ cal axis (102), wherein within the second Abbil ^¬ tion channel, a second optical deflection device (32) is arranged ^¬ formed to a relative to the second optical axis (102) transversely parallel offset (43) of the second optical axis (102).

The endoscope (1) according to claim 13, characterized in that the direction of the transverse parallel offset (43) of the second optical axis (102) is opposite to the direction of the transverse parallel offset (42) of the first optical axis (101).

15. endoscope (1) according to one of claims 13 or 14, since ^¬ characterized in that the second imaging channel (22) is designed as a projection channel (16).

16. Endoscope (1) according to one of the preceding claims, characterized in that the endoscope (1) has a Beobach ^¬ processing angle of 30 °.